Semi-explicit large eddy simulation in non-reacting air/gas fuel jet flows

Abstract

A Semi-explicit Large Eddy Simulation (SeLES) is proposed to help handle interactions between discontinuities and turbulence when using conventional Sub-Grid Scale (SGS) models of large eddy simulation. For the grid-scale simulation, the numerical viscosity becomes effective in the limited region detected by the discontinuity sensor, whereas a central difference scheme is applied elsewhere. In our SeLES, the discontinuous properties are considered in the SGS portion. Numerical tests are demonstrated for compressible coaxial jet flows of gas fuel and air without reaction. A comparison of the numerical results and experimental data confirms that this SeLES successfully prevents the overlap of numerical viscosity and SGS viscosity.